[PATCH -next v2] bpf/benchs: Fix return value check of bpf_program__attach()

[Yang Yingliang]

If bpf_program__attach() fails, it never returns NULL,
we should use libbpf_get_error() to check the return value.

Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx>
Acked-by: Yonghong Song <yhs@xxxxxx>
---
v2:
  don't use 'int err'
---
 .../selftests/bpf/benchs/bench_bloom_filter_map.c      | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/tools/testing/selftests/bpf/benchs/bench_bloom_filter_map.c b/tools/testing/selftests/bpf/benchs/bench_bloom_filter_map.c
index 6eeeed2913e6..4afaa4adb327 100644
--- a/tools/testing/selftests/bpf/benchs/bench_bloom_filter_map.c
+++ b/tools/testing/selftests/bpf/benchs/bench_bloom_filter_map.c
@@ -304,7 +304,7 @@ static void bloom_lookup_setup(void)
 	populate_maps();
 
 	link = bpf_program__attach(ctx.skel->progs.bloom_lookup);
-	if (!link) {
+	if (libbpf_get_error(link)) {
 		fprintf(stderr, "failed to attach program!\n");
 		exit(1);
 	}
@@ -321,7 +321,7 @@ static void bloom_update_setup(void)
 	populate_maps();
 
 	link = bpf_program__attach(ctx.skel->progs.bloom_update);
-	if (!link) {
+	if (libbpf_get_error(link)) {
 		fprintf(stderr, "failed to attach program!\n");
 		exit(1);
 	}
@@ -340,7 +340,7 @@ static void false_positive_setup(void)
 	populate_maps();
 
 	link = bpf_program__attach(ctx.skel->progs.bloom_hashmap_lookup);
-	if (!link) {
+	if (libbpf_get_error(link)) {
 		fprintf(stderr, "failed to attach program!\n");
 		exit(1);
 	}
@@ -358,7 +358,7 @@ static void hashmap_with_bloom_setup(void)
 	populate_maps();
 
 	link = bpf_program__attach(ctx.skel->progs.bloom_hashmap_lookup);
-	if (!link) {
+	if (libbpf_get_error(link)) {
 		fprintf(stderr, "failed to attach program!\n");
 		exit(1);
 	}
@@ -375,7 +375,7 @@ static void hashmap_no_bloom_setup(void)
 	populate_maps();
 
 	link = bpf_program__attach(ctx.skel->progs.bloom_hashmap_lookup);
-	if (!link) {
+	if (libbpf_get_error(link)) {
 		fprintf(stderr, "failed to attach program!\n");
 		exit(1);
 	}
-- 
2.25.1